Ecg leads placement

ECG electrode placement is standardised to record an accurate trace – but also ensuring comparability between records taken at different times. Poor electrode placement results in mistaken interpretation, possible misdiagnosis, patient mismanagement and inappropriate procedures. Start my subscription What is this article about? An electrocardiogram, or ECG, is a reading assessing the magnitude and direction of the electrical currents of the heart, and measuring the depolarisation and repolarisation of the cardiac muscle cells. It is important that an ECG is recorded accurately. ECG electrode placement is standardised, allowing for the recording of an accurate trace - but also ensuring comparability between records taken at different times. Poor electrode placement can result in mistaken interpretation, which may then lead to possible misdiagnosis, patient mismanagement or inappropriate procedures. Deviation of lead placement even by 20-25mm from the correct position can create clinically significant changes on the ECG, including changes to the ST-segment. Tom Walvin is a lecturer in adult nursing at the University of Plymouth, UK. Tom has a clinical background in Emergency Nursing, Cardiac Nursing, Pre-Hospital Care, Event Medicine and Clinical Research. His teaching interests are Deteriorating Patients, Emergency and Critical Care Skills, Resuscitation, Clinical Simulation, Pathophysiology, Anatomy & Physiology. Tom continues to work in clinical practice regularly sharing...

• • • • • • • • • • Telemetry is an observation tool that allows continuous ECG, RR, SpO2 monitoring while the patient remains active without the restriction of being attached to a bedside cardiac monitor. The patient group requiring telemetry are children diagnosed with a known/unknown arrhythmia, children at risk of an arrhythmia, or children anticipated to be at risk of sudden cardiac deterioration. Telemetry is not a replacement for patient visualisation and assessment. Telemetry accuracy relies on skin preparation, electrode and lead placement, equipment maintenance, patient monitoring and education. Studies have shown that with appropriate education to the patient and family, patient safety is improved and anxiety associated with monitoring is reduced. Nurses who are able to identify ECG abnormalities are in prime position to prompt immediate action and lessen patient complications. To guide safe and competent nursing and medical practice associated with the use of cardiac telemetry monitoring. • Telemetry – A portable device that continuously monitors patient ECG, respiratory rate and/or oxygen saturations while automatically transmitting information to a central monitor. • ECG – Electrocardiogram is a diagnostic tool that measures and records the electrical activity of the heart via electrodes placed on the skin. • Electrode – The patch that is placed onto the patient and attaches to the lead wire • Lead Wire- The lead that connects the electrodes to the telemetry ...

12-lead ECG • 10electrodes required to produce 12-lead ECG • 4Electrodes on all 4 limbs (RA, LL, LA, RL) 6Electrodes on precordium (V1–6) • Monitors 12 leads (V1–6), (I, II, III) and (aVR, aVF, aVL) • Allows interpretation of specific areas of the heart • Inferior (II, III, aVF)Lateral (I, aVL, V5, V6)Anterior (V1–4) 12-lead Precordial lead placement • V1: 4th intercostal space (ICS), RIGHT margin of the sternum • V2: 4th ICS along the LEFT margin of the sternum • V4: 5th ICS, mid-clavicular line • V3: midway between V2 and V4 • V5: 5th ICS, anterior axillary line (same level as V4) • V6: 5th ICS, mid-axillary line (same level as V4) Additional Lead placements Right sided ECG electrode placement There are several approaches to recording a right-sided ECG: • A complete set of right-sided leads is obtained by placing leads V1-6 in a mirror-image position on the right side of the chest (see diagram, below). • It can be simpler to leave V1 and V2 in their usual positions and just transfer leads V3-6 to the right side of the chest (i.e. V3R to V6R). V4R ECG lead placement Erhardt et al first described the use of a right sided precordial lead (CR 4R or V 4R) in the diagnosis of right ventricular infarction which had previously been thought to be electrocardiographically silent. [Single right-sided precordial lead in the diagnosis of right ventricular involvement in inferior myocardial infarction. Posterior leads Leads V7-9 are placed on the posterior chest wall in the following ...

There are three lead systems that make up the standard ECG: • Standard Limb Leads (Bipolar): I, IlI & III • Augmented Limb Leads (Unipolar): aVR, aVL & aVF • Precordial Leads: V1- V6 The Standard Limb Leads are used to display a graph of the potential difference recorded between two limbs at a time, ergo, they are bipolar. In these leads, one limb carries a positive electrode and the other limb, a negative one. The three limb electrodes, I, II and III form a triangle ( Einthoven’s Equilateral Triangle), at the right arm (RA), left arm (LA) and left leg (LL). The three Standard Limb Leads: Einthoven’s Law explains that Lead II’s complex is equal to the sum of the corresponding complexes in Leads I and III and is given as II = I + III For example, • If you had an ECG in which the Lead I R wave was 7mm tall and the S wave 2mm tall, subtract the S from the R, and you would have 5mm. • On the corresponding complex in Lead III, the R wave measures 1mm and the S has a negative deflection of 16mm. Subtracting the R from the S gives -15mm • In Lead II, using the same method as before, you get a measurement of -10mm Using these measurements with Einthoven’s Law you get • II = 5 + -15 = -10 So these leads are electrically equilateral. The Augmented Limb Leads obtain a graph of the electrical forces as recorded from one limb at a time using a null point with a relative zero potential, thus, they are unipolar. These leads, aVR, aVL and aVF give additional views on a trace by reading po...

• • Paediatric ECG lead placement • • Placement of paediatric ECG leads In young children, the right ventricle normally extends to the right side of the sternum. To appropriately display right ventricular potentials, ECGs for children in the under five-year age group must include an alternate lead ( ‘V4R’) on the right side of the chest, at a point analogous to the left-sided V4. Precordial leads: • V1: 4th intercostal space, right sternal border • V2: 4th intercostal space, left sternal border • V3: midway between V2 and the placement of V4 in adults (5th intercostal space, left mid-clavicular line) • V4R: 5th intercostal space, right mid-clavicular line. Use this lead for V4R, must label as such on ECG. • V5: anterior axillary line, same horizontal plane as V4 • V6: mid-axillary line, same horizontal line as V4 Limb leads: • Place on top part of arm or leg (less muscle interference)

• • Paediatric ECG lead placement • • Placement of paediatric ECG leads In young children, the right ventricle normally extends to the right side of the sternum. To appropriately display right ventricular potentials, ECGs for children in the under five-year age group must include an alternate lead ( ‘V4R’) on the right side of the chest, at a point analogous to the left-sided V4. Precordial leads: • V1: 4th intercostal space, right sternal border • V2: 4th intercostal space, left sternal border • V3: midway between V2 and the placement of V4 in adults (5th intercostal space, left mid-clavicular line) • V4R: 5th intercostal space, right mid-clavicular line. Use this lead for V4R, must label as such on ECG. • V5: anterior axillary line, same horizontal plane as V4 • V6: mid-axillary line, same horizontal line as V4 Limb leads: • Place on top part of arm or leg (less muscle interference)

• • • • • • • • • • Telemetry is an observation tool that allows continuous ECG, RR, SpO2 monitoring while the patient remains active without the restriction of being attached to a bedside cardiac monitor. The patient group requiring telemetry are children diagnosed with a known/unknown arrhythmia, children at risk of an arrhythmia, or children anticipated to be at risk of sudden cardiac deterioration. Telemetry is not a replacement for patient visualisation and assessment. Telemetry accuracy relies on skin preparation, electrode and lead placement, equipment maintenance, patient monitoring and education. Studies have shown that with appropriate education to the patient and family, patient safety is improved and anxiety associated with monitoring is reduced. Nurses who are able to identify ECG abnormalities are in prime position to prompt immediate action and lessen patient complications. To guide safe and competent nursing and medical practice associated with the use of cardiac telemetry monitoring. • Telemetry – A portable device that continuously monitors patient ECG, respiratory rate and/or oxygen saturations while automatically transmitting information to a central monitor. • ECG – Electrocardiogram is a diagnostic tool that measures and records the electrical activity of the heart via electrodes placed on the skin. • Electrode – The patch that is placed onto the patient and attaches to the lead wire • Lead Wire- The lead that connects the electrodes to the telemetry ...

ECG electrode placement is standardised to record an accurate trace – but also ensuring comparability between records taken at different times. Poor electrode placement results in mistaken interpretation, possible misdiagnosis, patient mismanagement and inappropriate procedures. Start my subscription What is this article about? An electrocardiogram, or ECG, is a reading assessing the magnitude and direction of the electrical currents of the heart, and measuring the depolarisation and repolarisation of the cardiac muscle cells. It is important that an ECG is recorded accurately. ECG electrode placement is standardised, allowing for the recording of an accurate trace - but also ensuring comparability between records taken at different times. Poor electrode placement can result in mistaken interpretation, which may then lead to possible misdiagnosis, patient mismanagement or inappropriate procedures. Deviation of lead placement even by 20-25mm from the correct position can create clinically significant changes on the ECG, including changes to the ST-segment. Tom Walvin is a lecturer in adult nursing at the University of Plymouth, UK. Tom has a clinical background in Emergency Nursing, Cardiac Nursing, Pre-Hospital Care, Event Medicine and Clinical Research. His teaching interests are Deteriorating Patients, Emergency and Critical Care Skills, Resuscitation, Clinical Simulation, Pathophysiology, Anatomy & Physiology. Tom continues to work in clinical practice regularly sharing...

12-lead ECG • 10electrodes required to produce 12-lead ECG • 4Electrodes on all 4 limbs (RA, LL, LA, RL) 6Electrodes on precordium (V1–6) • Monitors 12 leads (V1–6), (I, II, III) and (aVR, aVF, aVL) • Allows interpretation of specific areas of the heart • Inferior (II, III, aVF)Lateral (I, aVL, V5, V6)Anterior (V1–4) 12-lead Precordial lead placement • V1: 4th intercostal space (ICS), RIGHT margin of the sternum • V2: 4th ICS along the LEFT margin of the sternum • V4: 5th ICS, mid-clavicular line • V3: midway between V2 and V4 • V5: 5th ICS, anterior axillary line (same level as V4) • V6: 5th ICS, mid-axillary line (same level as V4) Additional Lead placements Right sided ECG electrode placement There are several approaches to recording a right-sided ECG: • A complete set of right-sided leads is obtained by placing leads V1-6 in a mirror-image position on the right side of the chest (see diagram, below). • It can be simpler to leave V1 and V2 in their usual positions and just transfer leads V3-6 to the right side of the chest (i.e. V3R to V6R). V4R ECG lead placement Erhardt et al first described the use of a right sided precordial lead (CR 4R or V 4R) in the diagnosis of right ventricular infarction which had previously been thought to be electrocardiographically silent. [Single right-sided precordial lead in the diagnosis of right ventricular involvement in inferior myocardial infarction. Posterior leads Leads V7-9 are placed on the posterior chest wall in the following ...

There are three lead systems that make up the standard ECG: • Standard Limb Leads (Bipolar): I, IlI & III • Augmented Limb Leads (Unipolar): aVR, aVL & aVF • Precordial Leads: V1- V6 The Standard Limb Leads are used to display a graph of the potential difference recorded between two limbs at a time, ergo, they are bipolar. In these leads, one limb carries a positive electrode and the other limb, a negative one. The three limb electrodes, I, II and III form a triangle ( Einthoven’s Equilateral Triangle), at the right arm (RA), left arm (LA) and left leg (LL). The three Standard Limb Leads: Einthoven’s Law explains that Lead II’s complex is equal to the sum of the corresponding complexes in Leads I and III and is given as II = I + III For example, • If you had an ECG in which the Lead I R wave was 7mm tall and the S wave 2mm tall, subtract the S from the R, and you would have 5mm. • On the corresponding complex in Lead III, the R wave measures 1mm and the S has a negative deflection of 16mm. Subtracting the R from the S gives -15mm • In Lead II, using the same method as before, you get a measurement of -10mm Using these measurements with Einthoven’s Law you get • II = 5 + -15 = -10 So these leads are electrically equilateral. The Augmented Limb Leads obtain a graph of the electrical forces as recorded from one limb at a time using a null point with a relative zero potential, thus, they are unipolar. These leads, aVR, aVL and aVF give additional views on a trace by reading po...